Representing a circular threshing floor covered with grain kernels. Sometimes it appears as two concentric circles, but more detailed renderings show tiny oblong kernels of grain in the inner circle and green markings on the outer circle. Late forms of the glyph render it as two short diagonal lines inside a circle. The phonogrammatic value of zp is derived by the rebus principle from its use as a determinative for a threshing floor, zpt.
